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I noticed the f bomb eliminator jet boat of Mike D has been rigged with the stringer rails laying on top of the stringers verses the conventional way of being bolted to the sides of the stringers. To me it seems like the most logical way to do it to keep the stress off the holes in the stringers. Does it really make a difference or is it just a preference?
 

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Engine Rails

Whenerver you build a light weight boat you always have a certian amount of movement in the hull. We have tried to eliminate as much movement in the intake and stringer area's as we could and this seemed the best way to do this. The K's have been doing it for years so I guess we can take a little vdrive knowledge and incorporate it into a jet boat.
 

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On my old rail kit, with a standard install, I was able to bend the rails after getting stuck in some rough stuff on Lake Mead. I considered going over the top of the rail with the new rail kit but in the end I decided against. I figured I shouldn't be out in such big water any more. Just goes to show that the design has its limitations.
 

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Why load the side of the stringer and not the top? You ever see a cracked stringer? Stringers are replaced all the time why not try to make them stronger? Stringers are designed to make boat more ridged so why not plate them and make them stronger?

A lot of the TAH have chassis to try and keep them as ridged as possible. IMO you do not want certain areas of the riding surface flexing. The deck and the sides only keep the water out LOL.

In theory a tunnel is a box beam design, more ridged than a v bottom anyways
 

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at the same time the boat should flex, and you putting a bunch of plating in to prevent it just means that stress is going to go elsewhere... i think theres a happy medium no?
A few years ago I built my own rail mounts with a piece of 4x4x3/8 angle ripped to 2x4, I built it with the 2x4 angle hanging on stringer. As a builder/carpenter this seemed like the the only logical way to proceed. Most people look at me with the facial expression of WTF, but after a minute it usually makes sense. I found out I did it backwards after finding PB via the interweb, but would still do it the same.:)sphss
 

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just had this talk with a friend the other day, i was thinking of capping my stringer with some plate aluminum by bending it in a "U" shape and putting it right over my stringers in the engine bay area. And then bolting my mounts to that just for extra rigidy to the stringers, anyone ever do this?
 

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at the same time the boat should flex, and you putting a bunch of plating in to prevent it just means that stress is going to go elsewhere... i think theres a happy medium no?
Just to clarify...I did not say that it is not the correct way to do things, I took note that Kboats have done this for years as a reply to the thread heading!
I run nowhere near the power that an UBFJ or Kboat runs, Not an issue for me!
In a light boat that is used as a race boat only?...sure the encapsulated stringer should (In theory) work out perfectly, will it stop the cracking of a stringer at the floor, I doubt it, there is a hard angle there, its a weak point, does it mean the boat is falling apart?....Absolutly not! there are stress release points all over boat designs, Vee bottoms, crack at the 4 corners of the gunnells (Usually at the rear), tunnels tend to crack between the sponsons up front, and where the stringers attach themselves to the floors, since owning a 19' tunnel and driving it through moderate chop, the boat does not flex at all the way a vbottom does, a tunnel flexes laterally (<---->) IMO, where a vee bottom takes a rough hit and it tries to peel the nose off from the bow! look at a lighter gullwing where the gullwings go fwd and meet the bow, there (Generally speaking) is significant cracking there, my Rogers had small cracking where the ribbon wrapped toward the nose at the capline, it honestly looked like it was trying to rip the nose off the boat with very small stress cracks.
I dont think that there is any way to stop a new or old boat, light or heavy, from stress relieving 100%, but then again, "why not" try to stop it from happening, which seems to me that MikeD and GS racing are doing.
Wonder if towing down I-40 or I-10 help these boats out? lol I bet it is the root of the problem, ever see the wear on the bottom of your boats, its not from launching!
 

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I was always told the reason the K's and circle jerks do it is for the load in the turns. It's more of a rigid mount and helps carry the side load better. 6to1 half dozon the other lol

As far as trailer towing damage, i have came up with a airbagged bunk system to let the boat float with the bunks rather then being just resting on the bunks. it will absorb more of the hit then just the springs on the axels. It's not been built yet, but it's in the works. It will take away alot of the hard "hits" that the roads seem to give our boats.
 

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I was always told the reason the K's and circle jerks do it is for the load in the turns. It's more of a rigid mount and helps carry the side load better. 6to1 half dozon the other lol

As far as trailer towing damage, i have came up with a airbagged bunk system to let the boat float with the bunks rather then being just resting on the bunks. it will absorb more of the hit then just the springs on the axels. It's not been built yet, but it's in the works. It will take away alot of the hard "hits" that the roads seem to give our boats.
Thats a good idea. most damage I get seems to be from tow
 

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Another pro for "over stringer" installation is that it allows better access to bilge area, starter, oil filter and all that other hard to get to stuff. If I ever rig another boat, will definately be over stringer........
 
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